Process of hydrogenation



Patented June 27, 1939' UNITED, STATES v I 2,163,603 PROCESS OFHYDROGENATION Leslie G. Jenness, Englewood, N. 1., a

or to Inter-metal Corporation, Newark, N. J., a corporation of DelawareNo Drawing. ApplicationFcbruary 4, 1938,

Serial No. 188,785 r 20 Claims.

This invention relates to the selective hydro-v genation of glycerideoils and more particularly to a process of selectively hydrogenatingglyceride oils which contain substantial quantities of fatty 5 acidradicals having more than two double bonds to produce products havingimproved keeping qualities. The present application constitutes acontinuation in part of my copending application Serial No. 44,635,filed October 11, 1935,

10 which is a continuation in part of my copending applications SerialNos. 13,973, 13,974, 13,975, and 13,976, all filed March 4, 1935.

This invention is particularly adapted for the conversion of glycerideoils having notoriously poor keeping qualities,' such as soya beanv oiland fish oils, into palatable liquid products having keeping qualitiescomparable to or exceeding those of the better vegetable oils, forexample, such oils as corn, sesame, or sunflower oils.

the thus treated oils to highly stable semi-solid fats of lard-like orbutter-like consistency'haw physical characteristics.

Olein is the most desirable constituent of the liquid oil. I have found,however, that the composition of the product on the basis of the totalfatty acid radicals present does not entirely determine keepingqualities. That is, I have found that products having substantially thesame fatty acid radical content and iodine number'may be prepared fromthe same original oil so as to have widely different keeping qualitiesdepending upon the method of preparation. This variation in keepingqualities in oils having the same composition with respect to the totalfatty acid radicals present, can only be explained on the basis thatmixed glycerides are formed by the present process and that an oilhaving the greatest number of mixed glyceride molecules has the greatestkeeping qualities.

It is, therefore, an object of the invention to provide a process ofselectively hydrogenatzng Also, the invention contemplates hydrogenatingthe liquid oil into a semi-solid fat havingproper glyceride oils havingpoor keeping qualities to produce liquid oils having high keepingqualities.

Another object of the invention is to provide a process of hydrogenatingliquid glyceride oils Another object of the invention is to provide aprocess for substantially completely converting unsaturates having morethan two double. bonds into lower unsaturates, at an early stage in theprocess, to enable the formation of olein containing mixed glycerides ina liquid oil. Another object is to provide a process of hydrogenating inwhich the hydrogenation reaction is maintained uniform throughout thebody of the I material being hydrogenated in order to prepare liquidoils having high keeping qualities fixed therein.

Another object of the invention is to control the agitation, rate ofhydrogen absorption, and contact of the hydrogen with the oil so as tomaintain the hydrogenation reaction uniform throughout the body ofmaterial being hydrogenated.

Another object is to provide a process of making semi-solid fats, suchas margarine or shortening, in which liquid glyceride oils containingfatty acid radicals'are first hydrogenated to fix high' keepingqualities therein while the oil is still liquid and then furtherhydrogenated to produce semi-solid fats having the desired physicalcharacteristics.

Another object is to provide a new liquid hydrogenated oil producthaving high keeping qualities.

A further object of the invention is to provide a process of forminghighly stable semisolid fats from said liquid-oil products.

A still further object of the invention is to provide a new hydrogenatedsemi-solid fat product havinghigh keeping qualities.

Other objects and advantages of the invention will appear in thefollowing detailed description of my invention.

The selective hydrogenation process of the pres ent invention for themaking of liquid oils having high keeping qualities is preferablycarried out in a closed chamber provided with agitating means andsuitable inlet and discharge passages for the oiland hydrogen. Anexample of a suitable apparatus is that disclosed in the patent toValentine No. 1,856,128. A suitable catalyst is employed and is mixedwith the oil, the mixture is agitated while being maintained at arelatively high temperature, and hydrogen gas is introduced into. thechamber, preferably under pressure so as to be dissolved therein andcarried throughout the body of the oil by the currents due to agitation.I have found that for selective hydrogenation it is important to carryout the process under conditions of high temperature, thoroughagitation, a relatively low rate of hydrogen absorption, and uniformityof hydrogenation reaction throughout the mass of oil being treated, andto employ a selective catalyst. The conditions of hydrogenation must besuch that unsaturates having more than two double bonds aresubstantially eliminated and the Wesson rancidity time of the liquid oilbrought to at least 10 hours by the time the iodine number has beendropped to The temperature at which the process is carried on has an'important effect upon the selectivity of the hydrogenation, In general,the higher the temperature, the more selective is the process towardhydrogenating the higher unsaturates and preventing the hydrogenation ofolein into stearin. However, higher temperatures also favor theformation of iso-olein. For this reason a catalyst which is selectivenot only against the formation of saturates but against the formation ofiso-olein is preferably employed. The temperature of hydrogenationcontemplated by this invention falls within a range from 280 to 380 F.and preferably between 300 and 330 F., the optimum temperature beingapproximately 320 F. I have found that a slow uniform reactionthroughout the mass of oil being treated is of great importance. Thenature of the agitation, the amount of catalyst employed, the rate ofgas absorption, and the hydrogen pressure as well .as the temperatureduring hydrogenation must be carefully correlated in order to produce aliquid oil having high keeping qualities from oils having unsaturateswith more than two double bonds.

An example of a suitable selective catalyst is the foraminate nickelcatalyst prepared by leaching with caustic soda and reducing aprecipitated and dried aggregate consisting of approximately 6NiOzCrOa,disclosed in my copending application Serial No. 13,972, filed March 30,1935. Another example of a suitable selective catalyst is the foraminatenickel catalyst prepared by leaching with caustic soda a dried aggregateprecipitated from a solution containing nickel sulphate and aluminumsulphate, the aggregate having a molecular ratio of NiO to A120: ofapproximately 13 to 1. This catalyst is also disclosed in my copendingapplication above referred to. Both of these catalysts are suitablealthough the former is somewhat more selective against the formation ofiso-olein. Certain other catalysts, for example, those known in thetrade as Formate catalysts or Raney catalysts, can be employed withfairly good results. With such catalysts considerable improvement overconventionally hydrogenated oils can be obtained by the presentinvention, but the stability of such oils does not approach thatobtained when the more selective catalysts first mentioned are employed.Any other suitable catalyst having the requisite selectivecharacteristics may be employed.

I have further found that there are at least two different types ororders of selectivity. The first is the recognized tendency of thehigher unsaturates to combine with hydrogen before the lowerunsaturates. The extent to which this type of selectivity may be carriedappears to be largely dependent upon the nature of the catalyst itselfas well as the conditions of hydrogenation. The highlyselectivecatalysts contemplated by the present invention, such as the foraminatecatalysts first mentioned, even under somewhat unfavorable conditionsproduce a much greater maximum olein content than the less selectivecatalysts under the most favorable conditions.

The second type, of selectivity is not concerned with the relative totalproportions of the various unsaturates in the resulting product butappears to affect selective hydrogenation within the glyceride moleculesand can be accomplished only by carefully controlling the conditions ofhydrogenation. I have found that the conversion of even one of the acidradicals of a normal unsaturated glyceride molecule into a radical ofless unsaturation makes this molecule more stable against hydrogenationat least in the presence of quantities of the lower unsaturate. Thus, ifthe reaction through the mass is made sufficiently slow and uniform;such mixed glyceride molecules are carried away from the catalyticsurface before being converted to a normal glyceride, and the normalglycerides of a given unsaturation are selectively converted into mixedglycerides. These mixed glycerides are not only more stable againstfurther hydrogenation but are also more stable against oxidation and aremore soluble in more stable lower unsaturates so as to be protected fromoxidation than are normal glycerides havingthe same degree ofunsaturation as the most unsaturated radical ofthe mixed glyceride.

By hydrogenating an oil containing glycerides having more than twodouble bonds under the conditions of uniformity of reaction contemplatedby this invention, it is possible to form a liquid oil in which all ofthe unsaturates having more than two double bonds have been hydrogenatedand substantially all of the two double bond unsaturates appear to bepresent as mixed glycerides. The resultant liquid oil is extremelystable and in general more stable than cottonseed oil. A stable oil canbe produced even though small amounts of three double bond acid radicalsshould remain in the oil. However, if such radicals are present in thehydrogenated oil, it tends to go off flavor" before rancidity develops,and when rancidity does develop, the characteristic odor of the oil alsodevelops. It is, therefore, desirable to completely convert all of theradicals containing more than two double bonds to lower unsaturates. Inaccordance with this invention, the linolenic content of soya bean oilcan be completely converted at an iodine number of 117 to 112, which isbefore any appreciable increase, in saturates occurs and while the oilis substantially as liquid as it was originally. Also in the case offish oils, the clupanodonic acids disappear along with their fish" odorat an iodine number of approximately 120 to 130, and the three doublebond acid radicals are completely converted at an iodine number at leastas high as 110.

The uniform slow reaction necessary to form mixed glycerides may besecured in various ways, all of which involve thorough agitation and a-low rate of gas absorption.

- -When employing a relatively large amount of catalyst, for example,0.2% ofthe weight of the oil, and relatively high hydrogen pressure, for

example, to 25 lbs. per square inch, any appreciable amount ofsplashing, in contact with an atmosphere of hydrogen, must be prevented.I have found that there is a tendency for the molecules in drops of oilor spray which carry suspended catalyst, to be completely hydrogenatedto lower unsaturates in the hydrogen atmosphere above the oil. Thisresults in the formation of normal glycerides instead of the desirablemixed glycerides. Thus, under the conditions mentioned, agitation shouldbe as intense as possible without causing splashing at the surface ofthe oil. An example of such agitation is that produced in an apparatussimilar to that shown in the patent to Valentine No; 1,856,128 havingtwo 6-inch impellers in a tank holding approximately 160 lbs. of. oil,with the oil covering the top impeller and the impellers rotating at aspeed just below that at which splashing occurs. A speed ofapproximately 300 R. P. M. was found to be suitable in a specificapparatus. By overloading the apparatusso as to bring the oilconsiderably above the upper impeller, it was possible to somewhatincrease the speed without splashing.

I have also found that the uniformity of reaction can be accomplished byusing a very small amount of catalyst and a low hydrogen pressure eventhough splashing occurs. In certain existing commercial installations ofhydrogenating apparatus, it is impossible to provide for thoroughagitation free from splashing without extensive, alterations in theapparatus. By using a' small amount of catalyst and a low hydrogenpressure, for'example', .05% catalyst and a hydrogen gauge pressure of 2lbs. per square inch, it is possible to slowdown the reaction in thespray in contact with the hydrogen atmosphere above the oil untillocalized concentrations are avoided and the reaction proceeds at asubstantially uniform rate throughout theoil.

It is also possible to overcome the rapid localized reactions due tosplashing by maintaining an atmosphere of an inert gas, for example,carbon dioxide, above the surface of the oil. One way of accomplishingthis is to mixa small amount of carbon dioxide with the hydrogenentering the hydrogenating apparatus. By regulating the amount ofhydrogen and carbon dioxide delivered to the hydrogenating apparatus, sothat hydrogen is substantially all combined with the oil, and directingthe mixture of gases into the lower portion of the body of oil, thecarbon dioxide collects above the oil and can be gradually bledtherefrom to maintain the proper pressure in the conversion chamber. Inthis manner a relatively large amount of catalyst (.2 to 25%) and arelatively high hydrogen pressure (10 to 25 lbs. per squareinch) may beemployedeven though the particular apparatus and rate of agitationcauses violent splashing. No local rapid reactions with consequentincrease in the formation of normal glycerides take place.

' general, fall within the range of 0.2 to 0.025%

by weight as disclosed in Serial No. 13,973 above referred to.

In order to secure uniformity of reaction and the formation of mixedglycerides, the rate of gas absorption must be maintained relativelylow. The more intense the agitation so long as there are no local rapidreactions due to splashing, the higher is the rate of gas absorptionwhich can be employed since the partially hydrogenated molecules aremore rapidly removed from the surface of the catalyst. Under givenconditions of temperature agitation and amount of catalyst, the rate ofgas absorption varies with the hydrogen pressure and can be convenientlyexpressed as the drop in iodine number per hour. It has been found thatthe approximate maximum rate of hydrogen absorption which results in theformation of, mixed rather than normal glycerides and therefore the bestpossible oil is a drop of 10 to 15 iodine numbers per hour dependentupon the conditions of hydrogenation. If all of the other conditions oftemperature, pressure, agitation, etc., are favorable, this rate ofhydrogen absorption can be exceeded and an oil having a Wesson time ofat least 10 hours at iodine number'prepared, especiallyif a relativelygood grade of oil is being processed. Thus rates equivalent to drops of17 or even 20iodine numbers per hour can sometimes be employed withother conditions favorable, if a it is desired to produce only anacceptable oil rather than the best possible oil. The importantconsideration is that the hydrogenation .rate

up to 50 lbs. per square inch, and probably higher and still enable anacceptable oil to be produced, by. decreasing the impeller speed belowthe 300 R. P. M. found to be just below the splashing point. It wasfound that a speed of 260 R. P. M. produced a rate of gas absorption 'ofapproximately 10 iodine numbers drop per hour at 50 lbs. per square inchhydrogen pressure and that a high keeping quality 011 resulted. Thus thehigher the hydrogen pressure, the lower the intensity of agitation mustbe in order to maintain the required rate of gas absorption. However,the intensity of agitation must not fall below that necessary to removepartially hydrogenated molecules of a given unsaturate from thecatalytic surface before they are hydrogenated to a normal glyceride ifthe high keeping quality oil is desired. Also the selectivity is not asgood as in the case of more intense agitation and lower hydrogenpressure.

Example I As a specific example, pounds of soya bean oil werehydrogenated at a temperature of 310 F.

and a pressure varying between 10 and 25 pounds per square inch.Approximately 0.2% of the catalyst made from the 6NiO2CrOa aggregate wasemployed and the mixture thoroughly agitated in a turbo mixer unithaving two 6-inch impellers revolving at 300 R. P. M., at which speedpractically no splashing occurred. The time of hydrogenation was onehour and fortyfive minutes, and the .drop in iodine number was 23,giving a rate of gas absorption of 13.1 iodine numbers per hour. Thehydrogen pressure was varied between the above limits to maintain thereaction slow and uniform.

The composition and iodine number of the original oil and productobtained were as follows:

It will be noted that the linolenin was completely converted; thelinolein content reduced from 54.7% to 35.1%; the olein contentincreased from 33% to 53.8%; thesaturated content remained substantiallyunchanged; and the linolein content decreased to less than two thirds ofits original content. The proportion of olein appearing as iso-olein wasless than 2%, which did not interfere with the oil being liquid at roomtemperature. The oil was extremely palatable and improved in color andshowed a rancidity test of approximately 14 hours as determined .by theWesson rancidity test at 212 F. This keeping time is superior to that ofthe best natural vegetable oils commercially obtainable Example II Asample of sardine oil was analyzed and found to contain 15 to 17% ofclupanodonic acid glycerides and approximately 6% of acid glyceridescontaining three double bonds. A charge of 160 lbs. of this sardine oilwas hydrogenated with .2% catalyst under the same conditions and withthe same catalyst as the previous example. The iodine number of theoriginal oil was 185, and this was reduced to 103 in approximately sevenhours such that the rate of gas absorption was approximately a drop of11.7 iodine numbers per hour. In such processes all of the clupanodonicacids disappear at an iodine number of approximately 140, and the threedouble bond unsaturates are substantially all converted at an iodinenumber of and completely disappear between an iodine number of 103 to107. The fishy odor of the original oil also disappears at the same timeas the clupanoclonic acids (about iodine number). This oil was entirelyliquid and showed a rancidity test of approximately eleven hours at aniodine number of 110. As to the keeping qualities, therefore, thishydrogenated fish oil is considerably superior to cottonseed oil.

The invention is also applicable to blends of fish and soya bean oil asshown in the following example:

Example III A charge of oil containing 120 pounds of neutralizedandbleached sardine oil and 4.0 pounds of neutralized and bleached soyabean oil, forming pounds of 75% fish oil and 25% soya bean oil, to whichwas added 2.72 pounds of completely hardened neutralized and bleachedsardine oil ch m - numbers per hour.

for plasticity control, was hydrogenated in the turbo mixer of Example Iwith an agitator speed of 304 R. P. M. at which substantially nosplashing occurred. The process was carried on at temperature of 320 F.in the presence of 0.15% nickel catalyst of the type used in Example Iand at a hydrogen pressure of 5 pounds per square inch. The charge washydrogenated from an iodine number of 165.8 to 107 at an average ratecorresponding to a drop of 13 iodine numbers per hour and the resultantliquid oil had a Wesson rancidity time of 12 hours so that the Wessontime was in excess of 10 hours at an iodine number of 110.

Example IV As an. example, using inert gas, a charge of 160 pounds of75% fish oil and 25% soya bean oil was hydrogenated at a gas pressure of35 pounds per square inch with 0.2 nickel catalyst of the same type asthat employed in Example I at a temperature of 300 to 310 F. and animpeller speed of 565 R. P. M., which was sufiicient to cause intensesplashing. The hydrogenating gas employed was approximately 75% hydrogenand 25% carbon dioxide and was introduced at the bottom of theconverter. In a very short time the free gas space above the oilconsisted practically entirely of carbon dioxide, which was graduallybled off while maintaining a gas pressure of 35 pounds per square inch.The time required to drop the iodine number from 171 to 103 was sevenhours or approximately 10 iodine The product was free from acid radicalscontaining more than two double bonds and hada Wesson rancidity time ofeleven hours.

Example V As another example in which a small amount of catalyst and lowhydrogenation pressure was employed to secure uniformity of reaction, a15,000 pound batch of soya bean oil was hydrogenated in a commercialhydrogenating plant. Since it was impossible, unless alterations weremade, to lower the speed of the agitating equipment below the splashingpoint and an inert gas was not available, a small quantity, 0.05%, ofthe 6NiOzCrO: nickel catalyst was employed and a hydrogen pressure of 2pounds per square inch gauge maintained. The oil was brought to 310 F.while mixed with the catalyst and the hydrogen introduced. A temperatureof 320 F. was maintained during the major part of the conversion. A timeof 1%; hours was required to bring the iodine number of the oil from 136to 113, which is a rate of approximately 15.3 iodine numbers per hour. Asample of this liquid product was tested and showed a Wesson ranciditytime of 16 hours after the usual steam deodori-- zation.

The liquid oil products made from oils containing unsaturates havingmore than two double bonds are free from such unsaturates at an iodinenumber of approximately 110 or higher and they have a Wesson ranciditytime of at least 10 hours at this iodine number, and, in general, havekeeping and shortening values greater than any known natural glyceride'oil. The keeping'tirne is in all cases greater than that of cottonseedoil, and the oils do not revert to a product having the characteristicodor of the original oil even at rancidity. While the liquid oilproducts resulting from the process of the present invention when usingprior catalysts such as the Formate" semi-solid fats.

or Raney catalysts have longer keeping times than any natural liquidoil, they do not approach in keeping qualities oils produced byemploying the more selective foraminate catalysts.

All of the liquid oil products of the. present invention have utility asliquid shortenings, salad oils, and compounding oils, from which to makeIt will be noted that the solid fat content is considerably smaller thanthat of naturaloils so that a much higher yield of salad oil isobtained. Also the liquid oil of high keeping qualities must first beprepared in order to produce semi-solid fats having high keepingqualities by further hydrogenation'or compounding with saturated fatsfrom other sources.

In making such semi-solid fats from the thus pretreated oils, thehydrogenation process may be carried on at a more rapid rate underconditions which result in a product of the desired consistency. Forexample, a rate of hydrogen absorption producing a drop of 40 to 50iodine numbers per hour has "been found satisfactory in practicealthough a lower rate of hydrogenation may be employed. Due to thepresence of the mixed glycerides and the fact. that high keepingqualities have been fixed in the pretreated liquid oil, any reasonablyselective catalyst can be employed for this portion of the process,although the more selective catalyst, the better will be the quality ofthe resultant fat. In practice it is preferred to use the highlyselective foraminate catalysts hereinbefore mentioned. The rapidhydrogenating process may be carried out without removing the oil fromthe pretreating converter by adding more catalyst and increasing thehydrogen pressure and agitation, or it may be carried out at asubsequent time in other apparatus. I have found that the keeping timeof the semi-solid fat produced from the pre-treated oil is dependentupon the keeping time of the pre-treated oil and the linolein content ofthe semi-solid fat. For soya bean oil,

this relation may be expressed approximately by the expression H=KL-iwhere H is the Wesson rancidity time of the semi-solid fat, L is thepercent of linolein in the semi-solid fat and K is a constant for anyparticular batch of pre-. treated oil. It will be noted that the keepingtime of the semi-solid fat decreases with an increase in linolein. Forthis reason pre-treated oils hydrogenated to the semi-solid state withordinary selective catalysts are somewhat inferior to those prepared byusing the highly selective catalysts since the linoleic content issomewhat higher.

The value of the factor K can be obtained from the semi-solid fat sinceH and L can be determined by test. It is equal to the Wesson. ranciditytime of the fat if hydrogenated to a linolein content of 1% since H isequal to K in the above equation if L is equal to 1. K has also beenfound to be a straight line function of the Wesson rancidity time of theliquid oil at 110 iodine number approximately in accordance with theexpression K .20.7h1'18, where his the Wesson rancidity time at 110iodine number. composition and Wesson time of the semi-solid fat.

The above relations do not hold for values'of h (Wesson rancidity timeat 110 iodine number) substantially below 10, that is to say for ,valuesof K-substantially below 90, nor for values of H (Wessonrancidity timefor a semi-solid fat in the margarine or shortening range) substantiallybelow 40. Below these values K is no cause of a very good pre-treatedoil.

The factor Thus h can be calculated from the.

longer a straight line function of h. and the pre-treated oil andsemi-solid fat have no substantial resistance to reversion, indicatingthat these values are critical. what different for fish oils but therequirement that the oil must be pre-treated so as to have a Wessonrancidity time of at least hours by the. time the iodine number has beenreduced to approximately 110 still holds.

Example VI ployed. The impeller speed was 565R. P. M.,;

and the hydrogen pressure was 25 lbs. per square inch. A time of onehour and five minutes was required to reduce the iodine number from 113to 64.7, at which time, the resultant semi-solid fat showed thefollowing characteristics and analysis:

The relations are some- Iodine number 64.7 Wiley melting point C 40.4Congeal point C 29.9 Wesson rancidity time hours 107 Saturates percent29.2 Olein do 68.0 linolein l. i. do 2.8

It will be noted that the linolein content is nearly 3%, yet the keepingtime is very highbe- This linolein content can be reduced to about 1% orless by carrying on the formation of semi-solid fats at a temperature of310 F.

Example VII As another specific example of the formation of semi-solidfats in accordance with this invention, the liquid oil resulting fromthe 15,000 pound batch of Example V and having an iodine number of 113and a keeping time of 16 hours was further hydrogenated at a more rapidrate without removing from the converter by adding 15% more of the samecatalyst, increasing the hydrogen pressure to pounds per squareinch,

and decreasing the temperature to 310 F. The hydrogenation then becamemore rapid, and the iodine number was reduced from 113 to approximately65 in about one hour. A semi-solid fat was produced, a sample of which,after laboratory deodorization, showed a Wesson .rancidity test time of208 hours. The product at this stage showed a Wiley melting point of39.2 C. and a congeal point of 30.6" C. The composition and iodinenumber were as follows:

Saturates percent 23.5 Total olein do.. 75.5 linolein do 1.0 Iodinenumber 65.2

Example VIII iii-exactly the same manner as in the previous example, thehydrogen pressure, amount of catalyst, and time of rapid hydrogenationbeing very nearly the same. A Wiley melting point of 38 C.

and a congeal point of 29.5" C. were obtained at an iodine number of66.7. The composition and iodine number of this product were as follows:

saturates per cent 22.9 Total olein do 76.3 Linolein do .8 Iodine number66.7

The keeping time of this product was 130 hours.

It will be observed that the compositions of semi-solid products of thelast two examples aresoya bean oil were pro-treated, in the apparatusemployed in the first specific example given in this specification, at atemperature of 310 F. and

hydrogen pressure of 10 lbs. per square inch. The impeller speed was 565R. P. M., and 0.05% nickel catalyst was employed. The iodine number wasreduced from 136.5 to 110 in two hours, which is a drop of 13.5 iodinenumbers per hour. The oil resulting from this pre-treatment was freefrom linolenin and had a Wesson rancidity time of 10 hours.

The above pre-treated oil was hydrogenated with .2% nickel catalyst at ahydrogen pressure of 25 lbs. per square inch, impeller speed of 565 R.P. M., and temperature of 300 F. for approximately 1 hour, at which timea semi-solid fat having the following characteristics and compositionresulted:

limit of semi-solid fats which can be considered to be of high keepingqualities or which have any substantial resistance to flavor reversion.The Wesson rancidity time of the liquid oil at 110 iodine number is just10 hours and the Wesson time of the semi-solid fat is but 38 hours.

Example X As another example of making a high keeping time semi-solidfat, a charge of 160 lbs. of sardine oil was hydrogenated in a convertersimilar to that shown in the Valentine patent above meritioned. Theimpeller speed was maintained at 300 R. P. M. during the pre-treatmentof the oil so as to prevent splashing, and .2% of the highly selectivecatalyst, first mentioned, was employed at a temperature of 310 F. and ahydrogen pressure of 15 lbs. per square inch gauge. The liquid oil hadan iodine number of 103 and a keeping time of eleven hours. Thetemperature was then reduced to 300 F., and the impeller speed increasedto 565 R. P. M. The hydrogenation was continued until the oil had aniodine number of 70.8, at which time its Wiley melting point was 37.0 C.and its congeal point 30.1 C. This semisolid product was of, lard orbutter-like consistency and had a Wesson rancidity time of 25 hours. Ingeneral, semi-solid fats from fish oils can be produced by the presentinvention having an iodine number below 80, a, melting point below 40C., and a keeping time between 25 and 30 hours.

Example XI As an example of producing a semi-solid fat from a blend ofsoya bean and fish oil, the liquid oil resulting from Example III wasfurther hydrogenated in the same apparatus with an impeller speed of 565R. P. M. with the same amount of catalyst at a temperature of 300 F. anda hydro-.

gen pressure of pounds per square inch in order to give desiredshortening characteristics. The iodine number was dropped from 107 to76.6 in 1% hours resulting in a product having a neutral flavor andcolor, a congeal point of 30.6 C. and a Wiley melting point of 38.4 C.The Wesson rancidity time was 45 hours, which is extremely high forproducts containing fish oil.

It is to be noted that, even by employing one of the better priorcatalysts such as the Formate or Raney catalysts in the process ofhydrogenation herein disclosed, both liquid oils and semisolid productsconsiderably better than known products result. However, such productsdo not approach those made by the present process when the highlyselective foraminate catalysts are employed. For example, by employingthe For- "mate catalyst in the present process, the linolenin can beeliminated from soya bean oil at an iodine number of approximately 105and with the Raney catalyst at an iodine number of approximately 95 anda semi-solid ,fat having higherkeeping qualities than known fatsproduced. However, by employing the highly selective foraminatecatalysts in the pre-treating stage and then the prior catalysts for therapid hydrogenation to a semi-solid fat, a much better product can beobtained. The distinction be-.

tween the prior catalysts and the foraminate catalysts is shown by thefact that even rapid hydrogenation, using this catalyst from theoriginal oil to the semi-solid fat without a pretreating step, producesa better product than any process in which the prior catalysts areemployed. By employing a pre-treating stage of hydrogenation followed byrapid hydrogenation, both with r the highly selective catalyst, aproduct having several times the keeping qualities of any fat made'byemploying the prior catalysts in any stage of the process results.

In the examples of oil or fat compositions given in this specification,the saturates, total olein, and linolein were determined from thethiocyanogen and the iodine numbers, both of which are obtained as aresult of titration methods, are more accurate than the older methodsinvolving fatty acid separation, and are standard methods at the presenttime. The iso-olein was determined by the Twitchell lead salt-alcoholmethod, which is a standard method at the present time. It is, ofcourse, understood that the original oils hereinbefore described hadbeen treated by the usual refining methods before hydrogenating and thatthe products of hydrogenation were submitted to the usual steamdeodorization before testing for edible properties. The Wesson ranciditytests were conducted under standardized conditions and checked againststandard oxygen absorption tests conducted at 100 C. with an air flow of2 cc. per second with observations of the rate of peroxide formation.The Wesson rancidity tests are well known tests for determining theOne-third of the length of the sheet was folded over the top of thedistributed oil or fat and the remaining third was then folded over thefirst one-third. The resulting strip was then rolled into a cylinder andplaced in'a 3 ounce margarine jar. The cap for this jar, with the paperlining thereof removed, was loosely screwed upon the jar. The jarcontaining the cylinder was then placed in a forced circulation electricoven held at 100 C. i 1 C. by a thermostat control.

The contents of the jar was smelled at frequent intervals to detect thebreak down point, which is determined by the presence of 'a definitely'rancid odor accompanied by the presence of acrolein and otheraldehydes.- The number of hours required to develop this rancidity pointis the Wesson rancidity time.

In this connection, it is noted that the best commercial semi-solid fatsprepared from cottonseed oil show a Wesson rancidity time of 18 hoursand an oxygen absorption test of 33 hours, while the semi-solid fatprepared from soya bean oil as herein disclosed and having a Wessonrancidity time of 208 hours showed an oxygen absorption test of 425hours; and that the rate of peroxide formation between various sampleswill bear the same relationship as the Wesson tests.

While I have described the preferred embodiment of my invention, it isto be understood that the invention is not limited to the detailsthereof but may be varied within the scope of .the following claims.

I claim:

1. In the process of making a semi-solid edible hydrogenated soya been011 product, the steps which comprise, hydrogenating said soya bean oilin the presence of a selective catalyst at a temperature between 280 and380 F., and at a hydrogenation rate not substantially greater than adrop of 15 iodine numbers per hour and with suflicient agitation toproduce a substantially uniform rate of reaction throughout the oilbeing hydrogenated to obtain an oil having a Wesson time not less than10 hours by the timethe iodine number of the oil has been reduced to110, and then further hydrogenating said oil in the presence of aselective catalyst to the semi-solid state thereby producing a semisolidfat characterized by having substantial resistance to reversion to thecharacteristic soya bean oil flavor. .2. The process of making a liquidedible hydrogenated soya bean oil which comprises, hydrogenataing saidsoya bean oil in the presence of a selective catalyst at a temperaturebetween 300 and 330 F., at a hydrogenation rate not substantiallygreater than a drop of 15 iodine numbers per hour and at a relativelylow pressure and catalyst concentration and with suflicient agitation toproduce a substantially uniform rate of reaction throughout the oil toobtain an 3. The process-of making a liquidedible'hydrog nated sova beanoil, which comprises hydrogenating said soya bean oil in the presence ofa selective catalyst at a temperature between 280 and 380 F., and at ahydrogenation rate not substantially greater than a drop of 15 iodinenumbers per hour and with suflicient agitation to produce asubstantially uniform rate of reaction throughout the oil beinghydrogenated to obtain an oil having a Wesson time of not less than 10hours by the time the iodine number of the oil has been reduced to 110,thereby producing a liquid oil having substantial resistance toreversion to the characteristic soya bean flavor.

4. In the process of making a semi-solid ediblehydrogenated soya beanoil product, thesteps which comprise, hydrog-enating said soya bean oilin the presence of a selective catalyst at a temperature between 300 and330 F., at a hydrogenation rate not substantially greater than a drop of15 iodine numbers per hour and at a relatively low pressureand catalystconcentration and with suflicient agitation to produce a substantiallyuniform rate of reaction throughout the oil to obtain an oil having aWesson time not less than -10 hours by the time the iodine number of theoil has been reduced to 110, and then further hydrogenating said oil inthe presence of a selective catalyst to thesemi-solid state, therebyproducing a semi-solid fat characterized by having sub- .stantialresistance to reversion to the characteristic soya bean flavor.

.hydrogenated to obtain an oil having a Wesson time not less than 10hours by the time the iodine number or theoil has been reduced to, 110,and then further hydrogenating said oil in the presence of. a selectivecatalyst to the semi-solid state,

thereby producing a semi-solid fat characterized by having substantialresistance to reversion to the characteristic soya bean oil flavor.

6. The process of making a liquid edible hydrogenated soya bean oil,which comprises, hydrogenating said soya bean oil inthe presence of aselective catalyst at a temperature between 300 and 330 F., and at ahydrogenation rate not substantially greater than a drop of 15 iodinenumbers per hour and with suflicient agitation to produce asubstantially uniform rate of reaction throughout the oil beinghydrogenated to obtain an oil having a Wesson time not less than10,hours by the time the iodine number of the oil has been reduced to110, thereby producing a liquid oil having substantial resistance toreversion to the characteristic soya bean flavor.

7. In the process of making a semi-solid edible hydrogenated productfrom oils containing substantial quantities of fatty acid radicleshaving.

more than two double bonds, the steps which comprise, hydrogenating saidoil in the presence of a selective catalyst at a temperature between 280and 380 F., and at a hydrogenation rate not substantially greater than adrop of 15 iodine numbers per hour and with suflicient agitation. toproduce a substantially uniform rate of reaction throughout the oilbeing hydrogenated to obtain an oil having a Wesson time not less than10 hours by the time the iodine number of the oil has been reduced to110, and then further hydrogenating said oil in the presence of aselective catalyst to the semi-solid state, thereby producing asemi-solid fat characterized by having substantial resistance toreversion to the characteristic flavor of the original oil.

8. The process of making a liquid edible hydrogenated oil from oilscontaining substantial quantities of fatty acid radicles having morethan two double bonds which comprises, hydrogenating said oil in thepresence of a selective catalyst at a temperature between 300 and 330F., at a. hydrogenation rate not substantially greater than a drop of 15iodine numbers per hour and at a relatively low pressure and catalystconcentration and with sufiicient agitation to produce a substantiallyuniform rate of reaction throughoutthe oil to obtain an oil having aWesson time not less than 10 hours by the time the iodine number of theoil has been reduced to 110, thereby producing liquid oil havingsubstantial resistance to reversion to the characteristic flavor of theorig-- inal oil. v

9. The process of making a liquid edible hydrogenated oil from oilscontaining substantial quantities of fatty acid radicles having morethan two double bonds which comprises, hydrogenating said oil in thepresence of a selective catalyst at a temperature between 280 and 380F., and at a hydrogenation rate not substantially greater ance toreversion to the characteristic flavor of the original oil.

10. In the process of making a semi-solid edible hydrogenated productfrom oils containing substantial quantities of fatty acid radicleshaving more than two double bonds, the steps which 7 comprise,hydrogenating said oil in.the presence of a selective catalyst at atemperature between 300 and 330 F., at a hydrogenation ratenotsubstantially greater than a drop of 15 iodine members per hour and at arelatively low pressure and catalyst concentration and with suflicientagitation to produce a substantially uniform rate of reaction throughoutthe oil to obtain an oil having a Wesson time not less than 10hours bying more than two double bonds, the steps which comprise, hydrogenatingsaid oil in the presence of a selective catalyst at a temperaturebetween 300 and 330 F., and a hydrogenation rate not substantiallygreater than a drop of 15 iodine numbers per hour and with sufiicientagitation to produce a substantially uniform rate of reaction throughoutthe oil being hydrogenated to obtain an oil having a Wesson time notless than 10 hours by the time the iodine number of the oil has beenreduced to 110, and then further hydrogenating said oil in the presenceof a selective catalyst to the semi-solid state, thereby producing asemi-solid fat characterized by having substantial resistance toreversion to the characteristic flavor of the original oil. I

'12. The process of making a liquid edible hydrogenated oil from oilscontaining substantial quantities of fatty acid radicles having morethan two double bonds, which comprises hydrogenating said oil in thepresence of a selective catalyst at a temperature between 300 and 330F., and a hydrogenation rate not substantially greater than a drop of 15iodine numbers per hour and with suflicient agitation to produce asubstantially uniform rate of reaction throughout the oil beinghydrogenated to obtain an oil having a Wesson time not less than 10hours by the time the iodine number of the oil has been reduced to110,-thereby producing a liquid oil having substantial resistance toreversion to the characteristic flavor of the original oil.

13. In the process of making a semi-solid edible hydrogenated productfrom a mixture of soya bean and fish oils, the steps which comprise,

hydrogenating said oils in the presence of a selective catalyst at atemperature between 280 and 380 F., and at a hydrogenation rate notsubstantially greater than a drop of 15 iodine numbers per hour and withsuflicient agitation to produce a substantially uniform rate of reactionthroughout the oil being hydrogenated to obtain an oil having -a. Wessontime not less than 10 hours by the time the iodine number of the oil hasbeen reduced to 110, and then further hydrogenating said oil inthepresence of a selective catalyst to the semi-solid state, therebyproducing a semi-solid fat characterized by having substantialresistance to reversion to the characteristic flavor of the originaloils.

141. The process of making a liquid edible hydrogenated oil from amixture of soya bean and fish oils whichcomprises, hydrogenating saidoils in the presence of a selective catalyst at a temperature between280 and 380 E, and at a hydrogenation rate not substantially greaterthan a drop of 15 iodine numbers per hour and with suflicient agitationto produce a substantially uniform rate of reaction throughout the oilbeing hydrogenated to obtain an oil having a Wesson time not less than10 hours by the time the iodine number of the oil has been reduced to110, thereby producing a liquid oil characterized by having substantialresistance to reversion to the characteristic flavor of the originaloils.

15. The method of producing a liquid oil having high keeping qualitiesfrom glyceride oils containing higher unsaturates than linolein, whichcomprlses'hydrogenating. said oils in the presence of 0.2 to 0.025 percent of nickel catalyst prepared by leaching chromium from and reducingan aggregate containing MO and ClOa combined in a ratio of approximately6 to 1, maintaining the temperature of the oil during hydrogenationbetween 280 and 380 F., agitating the oil during hydrogenation tomaintain a substantially uniform reaction throughout said oil, andmaintaining a hydrogen pressure on said oil suflicient to provide ahydrogen absorption rate not substantially greater than a drop of 15iodine numbers per hour.

16. The method of producing a liquid oil having high keeping qualitiesfrom glyceride oils con- .taining higher unsaturates than linolein,which comprises hydrogenating said oils in the presence of 0.2 to 0.025per cent of nickel catalyst prepared by leaching aluminum from andreducing an aggregate containing NiO and A1203 combined in a ratio ofapproximately 13 to 1, maintaining the temperature of the oil duringhydrogenation between 280 and 380 hydrogenation to maintain asubstantially uniform reaction throughout said oil, and maintaining ahydrogen pressure on said oil suflicient to provide a hydrogenabsorption rate not substantially greater than a drop of 15 iodinenumbers per hour.

17. The process of making a liquid edible hydrogenated soya bean oil,which comprises, hydrogenating said soya bean oil in the presence of aselective catalyst at a temperature above 280 F. and below that at whichsubstantial quantities of iso-olein are formed before an iodine numberof 110 is reached, and at a hydrogenation rate not substantially greaterthan a drop of 2,0 iodine numbers per hour and with sufilcient agitationto'produce a substantially uniform rate of reaction throughout the'oilbeing hydrogenated to obtain an oil having a Wesson time of not lessthan 10 hours by the time the iodine number of the oilhas been reducedto 110, thereby producing a liquid oil having substantial resistance toreversion to the characteristic soya bean flavor.

18. The process of making a semi-solid edible bean oil product whichcomprises, hydrogenating said soya bean oil in the presence of aselective catalyst at a temperature above 280 F. and below that at whichsubstantial quantities of iso-olein are formed before an iodine numberof is reached, and at a hydrogenation rate not substantially greaterthan a drop of'20 iodine numbers per hour and with sufiicient agitationto produce a substantially uniform rate of reaction throughout the oilbeing hydrogenated to obtain an oil having a Wesson time of not lessthan 10 hours by; the time the iodine number of the oil has been reducedto 110, and then further hydrogenatlng said oil in'the presence of aselective catalyst to the semi-solid state, thereby producing asemisolid fat characterized by having substantial re- F., agitating theoil during sistance to reversion to the characteristic soya bean flavor.

19. The process of making a liquid edible hydrogenated oil fromoilscontaining, substantial quantities of fatty acid radicals havingmore than tw fdouble bonds, which comprises, hydrogenating said oil inthe presence of a selective catalyst at a temperature'above 280 F. andbelow that at which substantial quantities of iso-olein are formedbefore an iodine number of 110 is reached, and at a hydrogenation ratenot substantially greater than a. drop of 20 iodine numbers per hour andwith sufliclent agitation to produce a substantially uniform rate ofreaction throughout the oil being-hydrogenated to obtain an oil havingWesson time not less than ten hours by the time the iodine number of theoil has been reduced to 110, thereby producing a liquid oil havingsubstantial resistance to reversion to the characteristic flavor of theoriginal oil.

20. The process of making a semi-solid edible hydrogenated product fromoils containing substantial quantities of fatty acid radicals havingmore than two double bonds, which comprises, hydrogenating said oil inthe presence of a selective catalyst at a'temperature above 280 F. andbelow that at which substantial quantities of isoolein are formed beforean iodine number of 110 is reached, and at a hydrogenation rate notsubstantially greater than a drop of 20 iodine numbers per hourand withsufficient agitation to produce a substantially uniform rate of reactionthroughout the oil being hydrogenated to obtain an oil having Wessontime not less than ten hours by the time the iodine number of the oilhas been reduced to 110, and then further hydrogenating 1 said oil inthe presence of a selective catalyst to the semi-solid state, therebyproducing a semisolid fat characterized by having substantial resistanceto reversion to the characteristic flavor of the original oil.

LESLIE G. JENNESS.

